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Making Penicillin: How Mold Saves Lives

Posted by, James on January 21, 2019

A Mold that Saves Lives

As we discussed in a previous blog, penicillin has quite the history. We’ve seen how it came about and learned about the minds of Ernest Duschene and Alexander Fleming. And we’ve discussed already a great number of different ways molds have formed by accident. But what if we’re looking to create mold? Well, that’s not so hard to do. Leave a piece of bread out in a humid environment long enough and you’ll start to see it happen. You can do this with any food item, but the big question is this: what if we’re looking for a specific kind of mold? What if the end of the world has happened and you need to make your own antibiotics? Well, there are ways you can make actual penicillin in your own home!

An Advance Warning!

I must STRONGLY STRESS though that though the experiment I’m going to cover will likely result in some penicillin. It will be just as how Fleming accidentally discovered it. That said, DO NOT TEST IT ON YOURSELF. You will get more than the mold that penicillin comes from. And there’s always the outside chance of risk with this. There’s also the fact that a lot of people also have an allergy to penicillin. Which can cause problems for them even if by some miracle you did get it. Laboratories around the world have special procedures and know how to make it at minimal risk. This is just an experiment that could be fun for a child’s science fair. Leave the real applications to the scientists!

Factory-Made Penicillin

Despite the section title, penicillin is made in labs. However, with changes in technology we’ve discovered way to make more and stabler penicillin for modern use. It was difficult to keep together until Howard Florey discovered a way to keep it stable. The process has changed little over the years. The primary means of making penicillin is fermentation. Nutrients for the mold gets sterilized and then fed into heated vats with the appropriate strain of mold. As we know, mold likes warm places and lots of food and moisture. These vats are designed to handle it! After about 40 hours, the mold begins secreting the penicillin for harvest. From there, it’s filtered, washed, and dried, and then it’s more or less ready for use. The companies that manufacture it then take it and clean it up a little. This includes additives to lengthen shelf life. Natural penicillin doesn’t have a long shelf life after all, so this helps ensure it’s ready to use at a moment’s notice.

Making Your Own

I won’t be going too in-depth into how you can make your own penicillin as discussed above. There are a lot of risks involved and there are also some legal aspects too. But, this can be an interesting little experiment if you want to carry it out. Since a lot of these ingredients are only available in bulk, it can be expensive. If you’re just doing this for a science fair experiment, talk to the teacher. They might have some of these and even help out. If you’re a minor, make sure to have some supervision like a teacher or parent help you out!

YES, many of these items (like hydrochloric acid) are potentially dangerous. Make sure you read up on this process and these products before you try this at home or in a lab.

Step 1:

Expose your chosen medium, be it bread or the citrus peel, to the air. Wait for it to get moldy. It’ll start grey. When it starts looking bright blue and green, then it’s time to harvest.

Step 2:

Sterilize one of the glass vessels. Putting them in an oven at 315 degrees should do the trick. Once sterile, drop the bright blue and green mold from your medium into it and seal it up. Incubate it for about a week, keeping the temperature around it at about 70 degrees. And then you’ll have your very own penicillin colony!

Step 3:

This is where it gets tricky as it is extracting the penicillin from your colony. Take 500 milliliters of cold water and put your chemical ingredients listed above into it. Then add more cold water until you have a full liter. From there, break out your test kit and the acid and tweak it with the acid until the solution’s pH value is between 5.0 and 5.5. Then scrape the spores off of your colonies from the previous part and drop it in! Leave it for seven days.

Step 4:

Finally, once the solution is ready, the penicillin will be floating in it. Now you filter it out and you’ll be left with penicillin! Ready for any science fair.

The Final Product

Remember what I said above though. DO NOT TEST THIS ON YOURSELF. If you want to see how it works, get a colony of bacteria together with an agar solution in petri dishes. And then try applying your newly made penicillin to some of them. You’ll notice that the ones that you don’t add penicillin to will have lots of colonies. Alternatively, the dishes with penicillin should not have as much or any mold!